Please refer to FIGS. 1A and 1B which are a perspective and a resolving diagrams schematically showing a conventional structure of a conventional vehicular interior rearview mirror. The rearview mirror includes a front housing 11, a rear housing 12, and a mirror 13 disposed between the front and the rear housings 11 and 12. The front and the rear housings 11 and 12 are conventionally made of a rigid plastic material such as polycarbonate (PC) or acrylonitrile-butadiene-styrene (ABS) resin for securing therebetween the mirror 13. As is known, due to both of the front housing 11 and the mirror 13 are inflexible, it is almost impossible for them to be in very close conjunction with each other. In other words, there is a certain level of gap existing between the housing 11 and the mirror 13. Therefore, the impact tolerance of the mirror 13 is adversely affected. Further, when a driver is seated in a vehicle, the interior rearview mirror has to be adjusted in order to have a proper view range from the mirror 13 while driving. The frequent manipulation of the rigid mirror housing 11, 12 would distort the mirror to some extent. The above-mentioned problems are even more serious when the housing material is aged due to long term exposure in the sunlight.
Compared to the interior rearview mirror that is generally planar, an exterior rearview mirror even more significantly suffers from the gap existing between the housing 11 and the mirror 13 due to its convex or aspheric (i.e. multi-radius) feature. As is known to those skilled in the art, it is relatively difficult to combine the housing with the non-planar mirror tightly.